The Manzanita Fire was reported shortly after 3 p.m. near Highway 79 and Dump Road, according to the Riverside County Fire Department.
Cal Fire officials said the cause of the brush fire was a single-car crash. Two people in the vehicle were hospitalized with unknown injuries.
The brush fire quickly grew from 125 acres at 4 p.m. on Monday to a massive 5,000 acres by midnight. The blaze was at 10 percent containment, fire officials said.
Northbound lanes of Highway 79 were still down to one lane.
Voluntary evacuations were issued for Highland Home, Death Valley and Longhorn roads, as well as Shirleon Drive. Evacuation warnings were also in place for Highland Home Road east of Highway 243, which includes the communities of Poppet Flats and Silent Valley.
Riverside County sheriff's officials said they "accidentally" put out evacuation alerts to residents in cities where there is no fire, including Norco, Corona and Jurupa Valley.
To stay up to date with evacuation warnings in the Riverside County area, visit rvcfire.org.